Our monthly series of ‘Vet View’ continues with Shona Young, from Westpoint Farm Vets in West Sussex, explaining the importance of quarantine and biosecurity.
With sheep sales well under way, farmers should know how to minimise the risk of introducing new diseases onto their farm, says Shona Young.
“Buying-in animals is one of the biggest biosecurity risks on any farm and an easy way to introduce diseases onto your unit, whether you have a beef, dairy or sheep enterprise.
“In an ideal world all breeding replacements would be home-bred and no animals would need to be bought-in, but sadly this just is not an option sometimes.”
Even farms which only buy-in a ram or bull occasionally need to consider the disease risks, Miss Young warns. Often these animals are bought in and put to work straight away as people do not consider they should be quarantined first, she says.
Having an appropriate quarantine protocol allows you to protect your herd or flock by trying to identify any existing disease in the purchased animals, and minimising the spread to your own animals, explains Miss Young.
“It is easier and much less expensive to reject one animal, or one group of animals, than have to suffer the consequences as an infectious disease spreads throughout your stock.
“For a disease like Johne’s, which has a long incubation period between infection and clinical signs, it could be years before you realise you have bought-in a problem.”
“Some farms do not know their own disease status, so you certainly do not want to complicate your situation by buying-in disease from another farm.
“Ideally you should source stock privately from farms of known disease status or accredited disease-free farms. For those who do know their disease status, vaccination of naïve bought-in animals may be necessary to protect them from the infectious diseases present on your farm,” advises Miss Young.
During the time they are kept in quarantine, the various tests, vaccinations and prophylactic treatments which have been agreed with your veterinary surgeon can be carried out, she adds.
Isolation facilities need to prevent contact between the bought-in animals and existing stock. A space of at least three metres (9.8ft) between them is required, advises Miss Young.
“If a building is used it should have its own separate airspace and if a field is used, double fencing may be required to prevent nose-to-nose contact.
“Facilities do not necessarily need to be solely dedicated to isolation, but they should be readily available when required and protocols for cleaning, disinfection and waste disposal should be in place for before, during and after their use.
Timing is vital, says Miss Young, animals should be isolated for at least three weeks, so buying in the week before you want breeding to start is less than ideal.
“When blood sampling animals, bear in mind it will take time for results to come back, and if vaccinating often two doses are required plus time for immunity to develop so you do need to be organised.”
With regards to parasites, treatment protocols should be in place, says Miss Young.
“Following Sustainable Control of Parasites in Sheep (SCOPS) guidelines for sheep, and Control of Worms Sustainability Strategy (COWS) guidelines for cattle, should help to prevent introducing resistant worms onto your pasture.
“It is important to consider if scab treatment should be given on arrival. This disease could very quickly spread through your flock and is especially important at this time of year.
“Remaining lambs may not need much longer to fatten and with the long meat withdrawals on treatments, is it worth the risk and expense?” asks Miss Young.
“This is a brief overview of the main risks to consider when buying in stock and basic guidelines to prevent introducing disease onto your farm. Every farm’s situation is different and so risks and protocols should be discussed with your own vet.”